Voters in Britain began casting their ballots on Thursday in the country’s most unpredictable national election in more than two decades.

Voters in Britain began casting their ballots on Thursday in the country’s most unpredictable national election in more than two decades.

Polls opened at 0600 GMT at around 50,000 polling stations across the UK, which will remain open until 21:00.

A total of 650 Westminster MPs will be elected, with about 50 million people registered to vote.

As well as the general election, there are more than 9,000 council seats being contested across 279 English local authorities.

British Prime Minister David Cameron is facing off against Ed Miliband, leader of the center-left Labour Party, and pollsters say the outcome of the vote is too close to call.

Opinion polls suggest that neither party is likely to win a majority of seats as voters defect to newly popular fringe parties.

With no clear winner expected, Friday could kick off days of political negotiations that would determine the country’s next leader.

The stakes are high: If Cameron’s center-right Conservative Party wins, the party will deliver a referendum on whether the U.K. should stay or leave the EU.

No other party has guaranteed this. Alternatively, a Labor government would likely rely on support from the Scottish National Party, which could use its leverage to argue for greater autonomy for Scotland.

The Conservatives have centered their campaign on their economic record, highlighting the U.K.’s recovery under their watch and accusing the previous Labor government of irresponsible spending. Cameron says only a Conservative government will keep the economy on track and continue to create jobs.